Starting a few years from when season 2 ended, the episode begins in a toy shop run by an old lady, who is sitting with closed eyes (perhaps asleep) does not notice a spider climbing its way from the ceiling, (presumably the boss of hell himself) to a shelter where a toy boy on a bicycle lies. The Spider walks to the boy's neck and the scene is covered by light. Right after that it is revealed that the toy boy on the bicycle has transformed into Kikuri.

The scene changes, moving to a bathroom probably made for animals where Ren Ichimoku works as a cleaner, and he sings as he works. A pound of water drops from the wet ceiling which startles Ren, making him look at the ceiling and commenting "It's cold." However as he turns his head he notices an undressed boy laughing at him and smiling. Though the scene is cut it can be assumed that Ren recognized the demonic nature of the boy by the way he says "You...". In later scenes, it is revealed that the boy's name is Yamawaro, Ai Enma's newest assistant.

As the scene changes again we see Kikuri riding her bicycle (at abnormally high speed) along the highway, to where Wanyuudou works as a builder riding a demolishing machine (perhaps his connection with vehicles made him choose that job). He is surprised to see Kikuri and when she tells him to follow him because "she" (Ai) is calling. Wanyudo practically steals the vehicle and follows her.

In the next scene we see Hone Onna working as a bar-woman in an empty bar, singing nostalgically. A bell rings, making her think it was the door, but seeing nobody concludes that is was nothing. As she sees an energy-made butterfly though she remembers with sadness Ai licking the water off a cherry. Her eyes become wet at the moment (obviously not realizing that the butterfly in front of her is Ai).

The scene of a classroom is shown right after that where the new protagonist of the series, Yuzuki Mikage, is copying from the black board. She is given a hand-drawn painting of her teacher with a roach's body and the word "annoying" written on it. Upon being discovered, the teacher notes that on his notebook and tends to the black board again. The real painter of the picture, a girl named Hiraishi, gets up and admits drawing the picture, and ask that what was noted about Yuzuki and her friend Akie be erased. The teacher ignores her. Hiraishi's dislike for the teacher becomes obvious from her expression.

She later discusses with Akie and Yuzuki about reporting the teacher to the principal, convinced that the failure of three earlier students to get to high school was caused by that notebook. Believing that they might be failed too she asks Akie (whose father is a high-ranking policeman with many connections) to report him. Meanwhile it is revealed that they are spied by Hone Onna in a gymnastics-teacher uniform. She is greeted by the teacher Ishimoto (Ren Ichimoku in science-teacher disguise).

We then see both of them as well as Wanyuudou in a house located at the hills discussing why Ai has returned. Kikuri appears accompanied with Yamawaro (who she uses as a personal servant). Kikuri announces they're back to "baldy" (Wanyuudou) and when he thanks Yamawaro for taking care of Kikuri she tries to catch Wanyudo's head with a fishing net. She stops right before that and asks Yamawaro to wind her up. It is therefore clear that Kikuri no longer possesses a living body. We then see Akie agreeing to help by talking to her father and then walking off with Yuzuki to their homes, (meanwhile they are followed by an energy butterfly which they do not notice).

The butterfly follows Yuzuki to her home. As night comes and Yuzuki is taking a bath, she notices the butterfly which melts, its glowing dust falling in the water. As the dust falls, Ai's face is reflected in the water. The lights go off and Ai herself emerges from the water, hugging Yuzuki and saying "It's cold." The room at that point becomes red, much like the color of Emma's eyes and the water takes a cyan colour, (reminding of a pool).

Ai drags Yuzuki to the water while energy flowers start blooming around the room. Under the water's surface Yuzuki is embraced by Ai and kissed, obviously surprised. When she opens her eyes, Yuzuki finds herself in the bathroom with the lights on again and no signs of Ai. As she wonders if it was a dream, she gets up scared and stares at the place of the bathtub where Ai had appeared. Without her realizing a cyan butterfly-shaped tattoo appears on her back.

The following day, Akie says that her father believed that, without evidence, any accusation would be pointless. She then apologizes and runs off. Hiraishi grabs Yuzuki's hand and tells her that they will create evidence to show to the principal. Hirashi plans on trapping the teacher to date her, and have Yuzuki take photos. Yuzuki trembles to the thought and states that doing that is not right, however Hiraishi acts to quick for her to do anything.

Much to Hiraishi's horror the one coming from the train isn't her teacher, but her parents who were informed by her teacher. Presumably after going back home, Hiraishi contacts Hell Correspondence. She immediately appears in Ai's realm, and Ai explains to her the usual procedure of how hell-sending works. Yamawaro transforms into a yellow straw doll, (by lowering his head and throwing a leaf above him) which Ai takes and gives to Hiraishi. Hiraishi complains about having to go to hell too, but wakes up in her room with the doll at the floor.

Yuzuki wakes up having seen what happened and when she wonders if it was just a dream, then Enma appears before her informing her that she is inside Yuzuki.

The next day Hiraishi is listening to her Mp3 while in classroom ( listening to the series' new opening song and thus breaking the fourth wall). Her teacher throws down her Mp3 and when she threatens him that he'll have to pay for it if it's broken, he collects it and takes it with him, while noting something in his notebook. After school, when everyone leaves, Hiraishi stays (with Yuzuki noticing so) and starts searching for her Mp3 in her teacher's items.

Her teacher catches her stating that he has thrown it away, he then proceeds to take out his notebook and starts writing on it. Hiraishi goes into an outburst accusing her teacher of bullying her and failing three students. She takes out the straw doll and her teacher laughs at her, saying she's watching too much anime (a reference to the show being an anime series and breaking the fourth wall again). She pulls the string and Yuzuki hurries into the room but in the way feeling pain in her back stops. The butterfly mark appears. We see her entering some kind of portal, and the butterfly on her back becoming a cocoon while she screams in pain. The rest of her body shatters with only the cocoon remaining and Ai hatching out of it. This would be the way Ai would emerge from Yuzuki's body for the rest of the season.

The teacher wakes up in a place full of numbers and is grabbed by an elephant shaped like number "two" (Ren). Ichimoku grabs the teacher and Ai appears as a bee, stinging Ichimoku who (like a normal elephant would react) throws the teacher to a distance. The rest of Ai's companions confront him. However,he states that he acts that way because he cares about his students' wellbeing. Ai's companions tell him that he should've been more careful with his students at that specific age because they're insecure and impulsive. Ai appears saying her usual "death quote" and a new kimono pattern. The teacher is then seen in the boat leading to hell with Ai rowing it.

A mark appears on Hiraishi's chest and Yuzuki runs in the room, with the teacher having disappeared. His notebook drops and Akie runs in giving Hiraishi her Mp3, telling her that the teacher had tasked Akie to return it to her. A gust of wind from the window flips the pages of the teacher's notebook revealing that there were, despite the students' thoughts, simply cartoon-like pictures drawn on it.

The episode closes with Yuzuko saying that the following day Hiraishi transferred schools (upon realizing that her teacher was innocent), and with the usual candle appearing.